shot in the dark, but it sounds like you're trying to install software
in a path that doesn't exist.
From MS Site:
<snip>
Path/File access error (Error 75)
See Also Specifics
During a file-access or disk-access operation, for example, Open,
MkDir, ChDir, or RmDir, the operating system couldn't make a connection
between the path and the file name. This error has the following causes
and solutions:
* The file specification isn't correctly formatted.
A file name can contain a fully qualified (absolute) or relative
path. A fully qualified path starts with the drive name (if the path is
on another drive) and lists the explicit path from the root to the
file. Any path that isn't fully qualified is relative to the current
drive and directory.
* You attempted to save a file that would replace an existing
read-only file.
Change the read-only attribute of the target file or save the
file with a different file name.
* You attempted to open a read-only file in sequential Output or
Append mode.
Open the file in Input mode or change the read-only attribute of
the file.
* You attempted to change a Visual Basic project within a database
or document.
You can't make design changes to the project.
For additional information, select the item in question and press F1.
</snip>
see:
http://msdn.microsoft.com/library/de...fileaccess.asp 
